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Theorem dral2 1966
Description: Formula-building lemma for use with the Distinctor Reduction Theorem. Part of Theorem 9.4 of [Megill] p. 448 (p. 16 of preprint). (Contributed by NM, 27-Feb-2005.)
Hypothesis
Ref Expression
dral1.1 (x x = y → (φψ))
Assertion
Ref Expression
dral2 (x x = y → (zφzψ))

Proof of Theorem dral2
StepHypRef Expression
1 hbae 1953 . 2 (x x = yzx x = y)
2 dral1.1 . 2 (x x = y → (φψ))
31, 2albidh 1590 1 (x x = y → (zφzψ))
Colors of variables: wff setvar class
Syntax hints:  wi 4  wb 176  wal 1540
This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-3 7  ax-mp 8  ax-gen 1546  ax-5 1557  ax-17 1616  ax-9 1654  ax-8 1675  ax-6 1729  ax-7 1734  ax-11 1746  ax-12 1925
This theorem depends on definitions:  df-bi 177  df-an 360  df-tru 1319  df-ex 1542  df-nf 1545
This theorem is referenced by:  drnf2  1970  equveli  1988  sbal1  2126  drnfc1  2505  drnfc2  2506
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